How to Use the Command 'git credential' (with examples)

The git credential command is an integral part of the Git ecosystem, aimed at simplifying the process of handling user authentication details. It interacts with various credential helpers to securely store, retrieve, and erase user credentials, thereby streamlining the workflow when accessing remote repositories. This command ensures that users don’t have to repeatedly enter authentication details, enhancing both convenience and security. Below, we delve into the specific use cases of this command, illustrating how it can be employed effectively.

Use case 1: Display Credential Information by Retrieving the Username and Password

Code:

echo "url=http://example.com" | git credential fill

Motivation:

This command is useful for users who need quick access to their stored credentials without manually searching through configuration files. For developers who frequently switch between repositories or work in environments where multiple credentials are managed, this command offers a streamlined way to verify existing credentials for a given URL. Knowing your credentials without manually delving into configuration files saves time and reduces the risk of human error.

Explanation:

• echo "url=http://example.com": This part of the command outputs the string containing the URL for which credentials need to be retrieved. In this case, we are specifying the repository hosted at http://example.com.

• |: The pipe symbol takes the output from the echo command and uses it as input for the subsequent command.

• git credential fill: This sub-command queries all available credential helpers for the corresponding username and password associated with the provided URL. The fill argument specifically instructs Git to populate and display the credentials back to the user.

Example Output:

username=yourUsername
password=yourPassword

This output indicates the credentials that are associated with the specified URL, http://example.com.

Use case 2: Store Credential Information for Later Use

Code:

echo "url=http://example.com" | git credential approve

Motivation:

Storing credentials for later use is a critical feature for developers working across different projects and repositories. Approving credentials via this command ensures that the user won’t be prompted repeatedly to enter their credentials when interacting with a given repository. This is especially useful for automated scripts or CI/CD pipelines where manual credential entry is impractical or impossible.

Explanation:

• echo "url=http://example.com": Similar to the first use case, this command constructs a string with the URL of interest.

• |: The pipe operator allows the URL input to be fed directly into the Git command sequence.

• git credential approve: The approve argument indicates that the credentials provided for the specified URL should be saved in the associated credential helpers. This adds the credentials to the system’s secure storage, making them readily available for future git operations that require authentication.

Example Output:

There is no direct output to the terminal, as the purpose of this command is to silently persist the credential information to the system’s credential store.

Use case 3: Erase Specified Credential Information

Code:

echo "url=http://example.com" | git credential reject

Motivation:

The need to purge credentials arises frequently in development environments, particularly when deprecating old credentials, preventing unauthorized access, or resolving authentication errors. By removing stored credentials, developers can prevent accidental use of outdated or compromised credentials, therefore safeguarding sensitive information and maintaining secure development practices.

Explanation:

• echo "url=http://example.com": As before, the echo command constructs a string that includes the URL whose credentials need to be resolved.

• |: The pipe forwards this constructed URL to the subsequent git command for processing.

• git credential reject: This component instructs Git to erase any credentials associated with the given URL from all configured credential helpers. The reject argument ensures that no outdated or unnecessary credentials remain in the system, thus allowing for secure credential updates or removals.

Example Output:

There is typically no output rendered to the console from this command. The result is an internal update to the system’s credential management, ensuring that credentials for http://example.com are removed.

Conclusion:

The git credential command is a powerful tool for managing user authentication details seamlessly within the Git ecosystem. Through commands like fill, approve, and reject, developers can efficiently manage access credentials, ensuring a balance between convenience and security when interfacing with remote repositories. Understanding and utilizing these commands not only saves time but also minimizes security vulnerabilities associated with manual credential handling.